html,body{
  height: 100%;
}
body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, sans-serif, "Apple Color Emoji", "Segoe UI Emoji",
    "Segoe UI Symbol";
  font-size: 16px;
  line-height: 1.6;
  margin: 0;
  padding: 0;
  color: #212529;
}

.container {
  display: flex;
  flex-direction: column;
  max-width: 960px;
  margin-right: auto;
  margin-left: auto;
  height: 100%;
}

h1 {
  min-height: 32px;
  margin-top: 0;
  margin-bottom: 0;
  font-size: 32px;
  font-weight: 400;
  text-align: center;
}

a {
  text-decoration: none;
  color: #0366d6;
}

article {
  display: flex;
  flex: 1;
  align-items: center;
}

article div {
  width: 100%;
  text-align: center;
  font-size: 2em;
  margin-top: -2em;
  display: flex;
  flex-direction: column;
  align-items: center;
}

footer {
  color: #1b1f23;
  border-top: 1px solid #e1e4e8;
}

footer div {
  margin: 1em 0 2em;
}
.button-3d-2{
  position: relative;
  background: #ecd300;
  background: radial-gradient(hsl(54, 100%, 50%), hsl(54, 100%, 40%));
  font-size: 1rem;
  text-shadow: 0 -1px 0 #c3af07;
  color: white;
  border: 1px solid hsl(54, 100%, 20%);
  border-radius: 100%;
  height: 60px;
  width: 60px;
  z-index: 4;
  outline: none;

  box-shadow: inset 0 1px 0 hsl(54, 100%, 50%),
              0 2px 0 hsl(54, 100%, 20%),
              0 3px 0 hsl(54, 100%, 18%),
              0 4px 0 hsl(54, 100%, 16%),
              0 5px 0 hsl(54, 100%, 14%),
              0 6px 0 hsl(54, 100%, 12%),
              0 7px 0 hsl(54, 100%, 10%),
              0 8px 0 hsl(54, 100%, 8%),
              0 9px 0 hsl(54, 100%, 6%);
}
.button-3d-2:active{
  top: 2px;
  box-shadow: inset 0 1px 0 hsl(54, 100%, 50%),
              0 2px 0 hsl(54, 100%, 16%),
              0 3px 0 hsl(54, 100%, 14%),
              0 4px 0 hsl(54, 100%, 12%),
              0 5px 0 hsl(54, 100%, 10%),
              0 6px 0 hsl(54, 100%, 8%),
              0 7px 0 hsl(54, 100%, 6%);
}